[WIP] Add SharedMemoryTracker to dump base::SharedMemory usage

base/memory/shared_memory_handle.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_MEMORY_SHARED_MEMORY_HANDLE_H_
 #define BASE_MEMORY_SHARED_MEMORY_HANDLE_H_
 
 #include <stddef.h>
 
+#include "base/trace_event/memory_allocator_dump_guid.h"
 #include "base/unguessable_token.h"
 #include "build/build_config.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #include "base/process/process_handle.h"
 #elif defined(OS_MACOSX) && !defined(OS_IOS)
 #include <mach/mach.h>
 #include "base/base_export.h"
 #include "base/file_descriptor_posix.h"
@@ skipping 135 matching lines @@
   static SharedMemoryHandle ImportHandle(int fd, size_t size);
 
   // Returns the underlying OS resource.
   int GetHandle() const;
 
   // Invalidates [but doesn't close] the underlying OS resource. This will leak
   // unless the caller is careful.
   int Release();
 #endif
 
+  std::string GetGUIDNameForTracing() const;
+
+  trace_event::MemoryAllocatorDumpGuid GetGUIDForTracing() const;
+
  private:
 #if defined(OS_MACOSX) && !defined(OS_IOS)
   friend class SharedMemory;
 
   Type type_ = MACH;
 
   // Each instance of a SharedMemoryHandle is backed either by a POSIX fd or a
   // mach port. |type_| determines the backing member.
   union {
     FileDescriptor file_descriptor_;
@@ skipping 23 matching lines @@
 
   base::UnguessableToken guid_;
 
   // The size of the region referenced by the SharedMemoryHandle.
   size_t size_ = 0;
 };
 
 }  // namespace base
 
 #endif  // BASE_MEMORY_SHARED_MEMORY_HANDLE_H_